Sanitary pump



June 27, 1950 R, W, HOOD 2,513,175

SANITARY PUMP Filed Aug. 7, 1947 4a n l k f E99 1. 68

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8 f l i Patented June 27, 1950 UNITED STATES SANITARY Roger W; Hood, Norwood,. Massa.lassignora.to` United American; Soda Fountain Corporation;V 1 Watertown,Mass a corperation"A ot vMassachu.-

setts Y Application August 7, 1947, V SerialNm"166,927i

(C1. I-L 1 3 Claims..`

Thiszinventionrelatesto dispensinglpumps, l andA is particularly concerned with that type ofpump` commonly u seddispensing beveragesat sodafountains, The pump in the present applicae tion, while kordinarily -used with beverages, never theles-sL can be' usedfwithrequalfacility in :the dispensing offany kind ofliquid.v

Pumpsqused f0r beverages, particularly for-v Syrups and -milk-gv must inthe interest ofA sani-tas tion'be cleanedA at short intervals. In thepumpse heretofore `usedfin this eldf', theconstructionsY are of such character-that adequate -cleaning-isl a` distinctly-diiiicult-,iob.` This is due to thefact that af substantial-'amount of timel is required for the dismantling-'and reassembly; whichl 'must be undertaken if the unit is tombe thoroughlycleanedf- Furthermore, the complexity-l of the parts-in themselves makes thorough cleaning a real problema drinking-f places.

more A thorough cleaning;

Accordingly,oneof the objects-of the-present! invention is to provide a construction which maybe so easily=-disassembled-and=c1eaned that theusers-lthereotwill notfind themselves'l reluctant to takethe'lunitapart and to perform the clean-`l ing operation; In` many localities oncialinspection-is frequently made; `The pump disclosed-- herein makes Y it possiblefwith minimumy inconvenience-and loss ottime to maintain thefrequiredi' sanitary standards.

A furtherobjectlof thef invention is to provide a constructionfso designed that all parts may be readily reached .with brushes commonly used for cleaningpurposes.. Another objectfof the.

invention is. to provide V`a dispensing -pump 4which permits easyand-l-quick removal of the'piston from the' cylindenso that all parts of the cylinder and pistonmay-be easily cleaned.'-

Another `object of thefy invention. is the provisionot a deliveryftube and nozzle soconstructed that 4allinterior-pipe sections` can-- be easilyand quickly` reached throughout ytheir 4entire l lengthsby the usel of: apipe-lorfftubecleaninglbrush Af further `oixect--o'f the invention is- -the provisionof closure@ means-y at upper- `endl of the delivery tube and at the outer-.en'dlot the'nozzl'ev of:v suchtcharacterlthatauponzremoval; afll ythose partskwhicha coxnewintoflcontactdwith the liquids'` willaliavesmooth .plane orcurvedsurfaces.. which may-be very.v Aeasilyfcleaned.;A While this constructionz contemplatesthe use-.- ot screw threads in `a-V nreferredl form, neverthelessfthe?,screw threads are sowlocated' as: to bei entirely out of range @of contactA with the't liquid-,1 so that" thev inadvertentiailurefto'clean the` thread will-noti be dangerous.` f

While l thef'nventi'0n'-1in thei accompanying drawings and-following description is disclosed as havinga particular pump handle arrangement, it will*r 'be'understoodI that the singularity. of radial' direction-of the pump.- handleA maybe varied accordance with the requirements of any given" installationg..

The inventiontwill be more'clearly understoodl as theV description proceedsI with the aid .of the accompanyingdrawings; in which Figsffl is a.:side elevation: of thepump, part`l being. in section and; part 4a side felevation The i parts have been broken awayjthrough a hori-y zontal section. to reduce the height ingu Figaz a. fragmentary; elevation similari to of the: draw- Figal, illustrating: the .'valve action during the descent of thepiston. v

' In accordance with common practicegrthepump I assemblyisg mountedon a5 container Icover plate 2, shapedb to close'A-properlyfthetop 4ofthe con-l tainer with .which theA pump is ausednand to provide a;suicientlysrigidsupport for normal opera. tal-.011...I

Descending i -from1 cover plate 2 .isiO a,N supporting' side .rod-l 4, rigidly mounted fon the.` under side offtheoplatefin any convenient. manner. Y .'Io the side oflthelower endfofa this rod. is secured, 11sual- 1y by. soldering; ,an inverted *open-ended' cylinder f 6, closed .at itstopl by. a disc 8-.. This disczhas'ztwo holesthroughit, oneaxially located :atl AI 0' and the other at the edge at l2. ;\flilxtending',upwardlyIV fromopening |12Y to the under side of plate-lis a delivery tube t4 which in thevpresentdisclosure terminates inf an internally-threaded' bushing i6.V y Into the upper endlof thisbushing is vthreadedE the lower extension lfofnozzle/Z. This=nozzle has `a #vertical portioniZ lf- `with afbore 22; the bore being an extension of and in alignment with delivery tube I4. A diagonally upwardly extending nozzle portion 20, having a bore 24 connecting with bore 22, leads away from portion 2|. Near the upper end of bore 24 is a downwardly directed tip 26, having a bore 21 that leads to the exterior from bore 24.

The pump mechanism comprises the cylinder 6; a piston 28 having a port 29, valve 30 that closes port 29, and piston rod 32 extending upwardly through the opening III which iits closely thereabout. 'I heoperating mechanism for the piston rod may be any conveniently arranged lever. In the form shown, there is a lever 34 pivoted at 36 on a forked support 35, with one arm 38 connected to the upper end of piston rod 32 by a will be at the bottom of its stroke, as shown in Fig. 1. Upward movement of piston rod 32 is limited by engagement of valve 3l)k with the closed upper end 8 of cylinder 6.

Asv shownin the drawing, the piston rod32 is straight and smooth throughout its entire length. The upper end of the piston rod vis slidably positioned in a bushing mounted on cover plate 2, as shown. Link 48 which connects the upper end of piston rod 32 to arm 38 may be removed from both elements by withdrawal of the two transversely extending pins, one of whichv passes through the upper. end of piston rod 32fand the other through the lower end of arm 38.

When link has been disconnected from piston rod 32,. it is obvious that the piston rod and its associated parts, namely, piston 28 and valve 30,'may be dropped downwardly out of cylinder 6 Another important feature of the invention-isv the construction designed to help insure cleanliness through ease ofvcleaning the closures at the upper end of the delivery tube and theupper end of the nozzle. Th'ese two closures are shown as being identical, although obviously the size of the respective parts might be varied. f

y The closure at the upper end of bore 22 of the nozzle extension of tube I4 comprises a cylindrical plug 54 having its lower end of a vdiameter that will fit snugly within bore 22. The central portion of the plug is of greater diameter, as at 56, providing thereby lower and upper. horizontal shoulders. The upper portion of the plug above the upper shoulder is of reduced diameter, which for yconveniencemay be made the same as that of the lower end. The lower shoulder of portion 56 ts snugly against the upper end of bore.22,.

andthe plug is held tightly in position by a collar 58 having an inturned flange 60 which engages the upper shoulder.y Collar 58 is in screw threaded engagement with portion 2| as at 59. By screwing collar 58 downwardly, plug 54 will be brought I into liquid-tight engagement with the upper end of bore 22, thereby effectively closing the top of the deliveryv tube. 1

The construction of the plug and collar at the outer end of nozzle20 is the same as that just described, and accordingly, the partshave been indicatedby the samenumbers. i

, Since plug 5,4 has its outer surfacecylindrical and smooth and the ends are flat. and." further.

since the ends of the portion 2| and nozzle 2 against which the lower shoulders of the enlarged parts 56 rest are likewise smooth and flat, it is obvious that the cleaning of these parts will be greatly facilitated. The liquid to be dispensed will come in contact with one end only of each plug when the pump is in use. It is believed that this arrangement entirely eliminates any possibility of contamination by the thread surfaces 59, should the latter be improperly cleaned.

While collar 58 is attachedto the'delivery tube and Anozzle by means of screw1 threads'still it will be understood that equivalent means could be v used without departing from the invention.

The delivery tube and nozzle for convenience have been made in two parts, with each part having a straight run therethrough to facilitate cleaning. It. will be understood, however, that the two could. be'made as a single unit with a single end closure,provided the curvature of the entire tube will permit passing a cleaning brush the entire length thereof.

rod 32 has beenmoved downwardly to that ,posi-v tion by spring 44.` Cylinder-6, being near the.

bottom of the container, -is, o i,course, completely' immersed in the liquid.` The area 50 within cylinder 6 will belled with liquidwhich has entered through the piston valve during the preceding downward stroke. `When the operator moves lever 34 to the left, as shown in dotted line position, piston 2 8, with, valve 30 closed, wi ll.move` upwardly to `drive liquidfrom the cylinder up through delivery tube I4 and out through tip 26 j of the nozzle. The maximum; vamount of liquid that can be delivered on a single stroke is substantially the volume of cylinder 6 contained above the piston.

Upon release of lever` 3 4, spring 44 will drive piston 28 downwardly, and in vso doingthe pressure of the liquid on the underside ofA piston V28 will force valve 30 to the diagonally cockedvposition shown in Fig. 2. i Valve 30 opens immediately upon the commencementof descent of piston 28, thereby'permitting liquid to flow through v the port29 of piston 28, andpastfvalve SI1-into the area 50 above the piston, r' I The opening of valve 30,;occurringsimultaneously with the beginning of the' descent of piston 28, insures that area 50 will be lledwith liquid, regardless of the yposition at which the downward movement of piston- 28 is commenced. When the piston 28 has descendedto bottom position, the level ofthe liquid vin'delivery tube I4 will be substantially that of, the liquid.` inthe container. Thus, only a small movement of lever'34 isrequired on a new vstroke before'the'liquid flows from the nozzle. 1' The eccentric locationof port 29 andthe tilting of valve 30"'which jamson-piston rod 32 rduring the down stroker is an important `feature of the invention. This construction not only provides for closure ofthe valve substantially simultaneously with the commencement of the upstrokevof the piston, but also causes thevalve Ato operate in a uniform manner on the downstroke.

When the piston starts downwardlypthe immediate cooking and jamming of .valve'3ll1on piston rod 32 insures that the valve will'maintain aconstant position regardless ofrthe rate' vof, descent and will be in positionfto-close, immediately upon the commencement of the next'A deliverystroke,

amenace whether that-suske. eltmnmencedzafter complete onpartial downward..,.movement of.; ,the.

piston. f, The'degree to which the'valv canft1ltlpn piston nod32 is determinedythe diameter lof the: centrally located ope'ning"through thevlve and. the.. thickness of the valve iat. the opening. These two factors obviouslyY determine th`disl tance between Ydiametricallyf"opposite portions of the periphery of the openinellld also thevanguf..

larity of thisdstancefwithfrespect; to thecilane of the valve. If the centrally located opening remains of constant diameter, then increasing the thickness of the valve at the opening will increase the distance between the diametrically opposite portions but will decrease the angle through which the valve disc may rotate. Conversely if the thickness of the valve at the centrally located opening remains constant and the diameter of the opening is increased, the distance between the diametrically opposite portions of the periphery will increase and the angle through which the Valve disc may be rotated will likewise increase.

If it is desired to maintain a constant maximum slanting angle of the valve, this may be done by adjusting the diameter of the opening to the thickness of the valve at the opening. In all cases, however, it is desirable that the extent of the valve opening be relatively limited so that closing of the valve will occur upon very slight upward movement of the piston at the commencement of the discharge stroke.

In further explanation of the foregoing, it is pointed out that if, for example, there was another port 29 located at 180 from the present port 29, then downward movement of the piston would result in valve 3U lagging behind as it gradually floated down through the liquid. That is to say, unless the valve 30 is positively carried down by the piston, it would lag behind the piston in varying amounts, depending on the rate of piston descent. Such lagging would cause variable amounts of liquid to be delivered if upward movement of the piston commenced before the valve had seated.

It may therefore be stated that the construction of the present valve provides for closure of the orice coincidental with the beginning of upward piston movement, where the latter is actuated immediately following a downward stroke. Of course, it will be understood that if the piston has been allowed to come to rest, valve 30 will settle at once on the piston to close port 29, which condition will be present at the start of any subsequent delivery stroke.

While the invention has been described with reference to a preferred form, it is not to be limited thereby, but only by the appended claims.

I claim:

l1. Piston and valve mechanism for use in a beverage pump comprising a cylinder open at one end, a piston rod having mounted thereon a circular disc forming a piston, said piston fitting closely within said cylinder and removable therefrom through said open end without modiiication of said cylinder, a passage through said piston, all of said passage being on one side of a diameter of said piston, a second disc forming a valve and resting on the top of said piston with the piston rod extending throgh a centrally located opening in said valve, said centrally located opening being larger than said piston rod, said valve being of less diameter than said piston but large enough to overlie said passage to close the latter, that pohtionlofttheizpstbrr mdmiitliinsaidfcylinden 13B-'r wardlyutoraf slanting fp ositiorr underA .theinfluence 1` saidfipistomfpassage, iagainstethec under, sidactsaida-valyegtheimovementnf said: .valve.c along; .said pistmrodi'b'einglmited solelyfbyvengagment of diametricallyinppositewpertions fofs'fthernernhery orlsaidiopening againstfsaidvpiston; dttheedisei tance between the said;damgtricallyopmsiteip91;-f tionsaoflthe'iperplieric'of said opening being controlled by the diameter of said centrally located opening and thethi'cknes'sLof saidlvalve disc at said openingjsaid distancedetermillngthe angle of the maximum slanting positionoff.saidvalveg 2. Piston and valve mechanism lfor use in a` beverage pump comprising a cylinder open at one end, a piston rod having mounted thereon a circular disc forming a piston, said piston fitting closely within said cylinder and removable therefrom without modification of said cylinder, a passage through said piston, all of said passage being on one side of a diameter of said piston, a second disc forming a valve and resting on the top of said piston with the piston rod extending through a centrally located opening in said valve, said centrally located opening being larger than said piston rod, said valve being of less diameter than said piston but large enough to overlie said passage to close the latter, that portion of the piston rod within said cylinder being straight and smooth, the thickness of said valve at the periphery of said centrally located opening in relation to the diameter of said opening and the diameter of said piston rod being such as to limit upward movement of said valve caused by the pressure of iluid owing upwardly through said piston passage against the underside of said valve to a slanting position not greater than an angle of thirty degrees to the plane of said piston, the aforesaid movement of said valve with respect to said piston and piston rod being controlled by the engagement of diametrically opposed portions of the periphery of said opening against said piston rod, the distance between the said diametrically opposed portions of the periphery of said opening being controlled by the diameter of said centrally located opening and the thickness of said valve disc at said opening, said distance determining the angle of the maximum slanting position of said valve.

3. Piston and valve mechanism for use in a beverage pump comprising a cylinder open at one end, a piston rod having mounted thereon a circular disc forming a piston, said piston fitting closely within said cylinder and removable therefrom without modication of said cylinder, a passage through said piston, all of said passage being on one side of a diameter of said piston, a second disc forming a valve and resting on the top of said piston with the piston rod extending through a centrally located opening in said valve, said centrally located opening being larger than said piston rod, said valve being of less diameter than said piston but large enough to overlie said passage to close the latter, said piston rod being straight and smooth throughout its entire length whereupon when said piston and piston rod have been removed from said'cylinder through said open end, said valve may slide freely along the entire length of said piston rod, said valve when in operative position on said piston movable upwardly to a slanting position under the influence of the pressure of fluid flowing upwardly through said piston passage against the underside of said valve, the movementof said valve caused by said owingiiuidbeing limited solely by engagement of opposed positions'` of the periphery of said opening Aagainst said piston rod, the distance be'- tween the said opposed portions 0f the periphery of said opening being controlled by the diameter of said centrally located opening and thexthickness of said valve disc at said opening, said distance determining the angle of the maximum slanting position 'of said valve.

ROGER W. HOOD.

REFERENCES CITED The following references are of record in the file'` ofY this patent:

8 UNITED STATES PATENTS Number Number Name Date Dowling Sept. 21', 1875 p smith sept. 29, 1891 Fletcher June 5,1923

Alvey Aug. 6, 1929V Babin Feb. 18, 1930 FOREIGN PATENTS Country Date Great Britain --.Nom 11, 1938 

